Improved hoisting-gear



dem ,eine

utenti (Lemire.

Lena-s 'Patent No. 102,719, met May 3, 1ero.

IMPROVED HoIsTrNG-GEAR.

The Schedule referred to in these Letters Patentand making part of thesame of which the following, taken in connection with the accompanyingdrawings, is a specification.

Nature and Object of the Invention.`

The subject-matter of my invention relates to an improvement upon aformer invention of mine, described in Letters Patent granted to meMarch l0, 1868, and numbered 75,304, which consisted of two drums orcylinders mounted upon two eccentrics, placed diametrically opposite toeach other' uponthe same shaft, one of said drums having 'an internalspur-gear formed in its side, and the other drum being provided with anexternal spur-gear of a somewhat smaller diameter, which meshes into theinternal gear, and, by the action of the eccentrics, the two gears aremade to roll upon each other, and, by virtue of theresistance presentedby the load, which is suspended by two ropes depending from oppositesides of said drums, they are made to revolve in opposite directions,raising the load when the eccentric shaft is revolved in one direction,and lowering the load when it is` revolved in the opposite direction.'

For certain purposes, such, for instance, as operating the carriage ofpassenger-elevators, this arraugement has been found to beobjectionable, on. account of the vibratory or shaking motiontransmitted to the carriage and platform, by the oscillating motiongiven to the periphery of the drums by the action of the eccentrics.

To obviate this objection and cause lthe two hoistving-drums to revolvein opposite directions 'and coucentric with the actuating-shaft, so asto produce a perfectly steady and constant motion for raising the load,and at the same time, be perfectly self-sustaining in any position, isthe object of my present in'- vention. v

My invention consists in the arrangement of two hoisting-drums, side byside upon the same shaft, to each of which, upon sides opposite to eachother, is attached a hoisting-rope so connected to the load to be raisedthat each of said drums shall sustain half the weight, said drum beingsofitted to said shaft as to be free to revolve thereon,` and having aninternal spur-gear formed in each of their 4contiguous ends of differentdiameters, but both concentric to the shaft on which they revolve, saiddrums being operated by the action of two external spur-gears ofdiierent` diameters, bolted or riveted firmly together, or cast in onepiece so as to become practically one gear, andv mounted upon a singleeccentric upon the same shaft upon which the drums are mounted, andbetween said of the internal gears, and the other half into the otherinternal gear, as shown, each of said internal gears, with the loadattached thereto, servingas a vfulcrum for the planet-wheel]7 orspur-gear mounted'upon the eccentric, to act upon to revolve the otherdrum, and rice tersa.

Instead of the gears J and K, made as described, a single spur-gear,withl teeth out parallel to each other across the whole face of thesame, may be used, the internal gears on the winding drums being made ofequal diameters, but having a different number of teeth, and thesameresult be obtained without changthe principle of operation. l

Description of the Drawings.

Figure 1 is a front elevation of an elevator with my' improvementsapplied; y v

Figure 2 is a side elevation of the same;

Figure 3 is a longitudinal section through center of drums and th'egearing, showing the shaft and eccentric in elevation;

Figure 4 is a-transverse section through the shaft and eccentric on linex z' on g. 3, and showing one of the drums, its internal gear,'and thathalf of the external gear which opera-tes therewith in the elevation;

and

Figure '5 is a section on the' same line, and showing the other drum andits gearing ir jievation.

. General Description. A A are the guiding-posts of the elevator; B, theframe of the carriage; and C, the platform.l D is across-bar secured tothe top of the carriage, and to which the lower ends of the ropes E andF are attached, one at either end, the other end of said ropes beingsecured to the periphery of the drums G and H upon opposite sidesthereof, as shown, the rope E connecting with the drum G, and the rope Fwith the drum H.

The drums G and II are fitted loosely to the shaft I7 so that they arefree to revolve thereon, and have an internal gear formed in each oftheircontiguous 'ends,'the pitch circles oi' which are concentric withthe shaft I.

J and K are two spurl-gears riveted firmly together lupon a singleeccentric, L, their pitch circles being of Y different diametersandeccentrie to the shaft I.

Y M M are hangers to support the shaft I near the point where the loadis applied.

N is a crank, by means-ofwhich the shalt I may'U be rotated.

The operation of my improved-machine is as follows:

The partsbeing in the position shown in the drawings, and the load beingsuspended in the manner described, so as to be equally divided betweenthe two drums, it will readily be seen that the tendency of the load tocause the two ,drums to revolve in opposite directions will cause theteeth in the upper portion ot the internal gear in the drum G to presshard against one side of the teeth inthe upper portion ot' thcspur-gearJ., and, if not resisted by a counter pressure, would cause the gear Jto revolve in the direction in which said pressure is exerted, and theload would run down, but it 4will be seen that the teeth in the upperportion of the internal gear in the drum H press with equalforee uponthe opposite side ofthe teeth in the upper portion of the spur-gcar K toturn that in the opposite direction, and thusthc tendency of one drum torevolve, just counteracts the tendency ot' the other to revolve in theopposite direction, and the load is held in suspension.

1Now, if the shaft I be revolved in the direction of arrow, theeccentric L will rotate in the gears J and K, and cause theirpoints ofcontact with the internal gr ar to travel around the shaft, the gearsthemselves heilig kept from revolving by virtue of the tendency ot' theload to descend, (caused by gravit-y,) act-ing uponr said drums to causethcln to revolve in opposite directions, and, as aresult ot' saidchanging of thev point ot' contact, in combination with the differencein diameters, and number of teeth in the several gears, both druins willbe revolved in opposite directions in a path concentric to the shaftupon which they are mounted,and wind the ropes upon their peripheries,and thus raise the load, the motion being perfectly steady andV freefrom any unpleasant jar or vibration.,

By reversing the motion of' the shaft the action is reversed and theload will be lowered.

Having t-hus fully described my improvement,

What I claim as new and desire to secure hy Letters Patent ot' theUnited States, is Y i The drums G and H mounted upon the saine shaft,each being provided with an internal gear and sustaining half theload tobe raised, when said drums are made to revolve in opposite direct-ions`by the action of a single spur-gear mounted upon au eccentric upon theactuating-shaft, substantially as described.

Executed at Boston' this 23d day of February, 1870.

HENRY F. SHAW'.

Witnesses D. B. I-l'lxsson,l G. F. WHITNEY.

